3d printing system for preparing a three-dimensional object with an autoclave

Abstract

A three-dimensional printing system for preparing a three-dimensional object made at least partially of an expanded polymer includes an autoclave, a printing device and a three-dimensional movement device. The printing device prepares an expandable polymer melt and deposits a strand of the expandable, expanding or expanded polymer onto a surface. The three-dimensional movement device adjusts the position of the printing device in a predefined three-dimensional matrix so as to enable depositing of the strand of expandable, expanding or expanded polymer at a predetermined time at a precise position within the three-dimensional matrix. The printing device includes a feed section, a cooling section, a backflow prevention section, a heating section and a terminal printing head section including a die for depositing the expandable, expanding or expanded polymer strand onto the surface.

1 . A three-dimensional printing system for preparing a three-dimensional object made at least partially of an expanded polymer, comprising:
 an autoclave;   a printing device configured to prepare an expandable, expanding or expanded polymer melt and deposit a strand of the expandable, expanding or expanded polymer onto a surface; and   a three-dimensional movement device configured to enable depositing of the strand of expandable, expanding or expanded polymer at a predetermined time at a position within the three-dimensional matrix,   the printing device comprising:   a feed section,   a cooling section,   a backflow prevention section,   a heating section, and   a terminal printing head section including a die configured to deposit the expandable, expanding or expanded polymer strand onto the surface.   
     
     
         2 . The three-dimensional printing system in accordance with  claim 1 , wherein the autoclave is configured to resist a pressure of up to 150 bar and a temperature of up to 300° C. 
     
     
         3 . The three-dimensional printing system in accordance with  claim 1 , wherein the autoclave is connected directly or indirectly with the feed section of the printing device so that an expandable polymer mixture prepared in the autoclave is capable of being transferred from the autoclave directly or indirectly into the feed section of the printing device. 
     
     
         4 . The three-dimensional printing system in accordance with  claim 3 , wherein the autoclave is connected directly with the feed section of the printing device so that an expandable polymer mixture prepared in the autoclave is capable of being transferred from the autoclave directly into the feed section of the printing device. 
     
     
         5 . The three-dimensional printing system in accordance with  claim 3 , wherein a conveyor is arranged between the autoclave and the feed section of the printing device, so that the expandable polymer mixture prepared in the autoclave can be transferred from the autoclave via the conveyor into the feed section of the printing device. 
     
     
         6 . The three-dimensional printing system in accordance with  claim 1 , wherein at least one of the feed section, the cooling section, the backflow prevention section and the heating section are tubular sections having a same inner diameter as at least one of an other of the feed section, the cooling section, the backflow prevention section and the heating section. 
     
     
         7 . The three-dimensional printing system in accordance with  claim 1 , wherein the feed section, the cooling section, the backflow prevention section, the heating section and the printing head section are arranged in this order from an upstream end to a downstream end of the printing device. 
     
     
         8 . The three-dimensional printing system in accordance with  claim 1 , wherein the cooling section or the heating section or the cooling section and the heating section are a tubular section comprising a tube, and a Peltier element, a heat exchanger or cooling fins are disposed on an outer wall of the tube. 
     
     
         9 . The three-dimensional printing system in accordance with  claim 1 , wherein the backflow prevention section is a tubular section, an inner diameter of at least a part of a length of the tubular section is smaller than an inner diameter of the cooling section and the heating section. 
     
     
         10 . The three-dimensional printing system in accordance with  claim 1 , wherein the printing head section is a tapered tubular section, the downstream part of the printing head section is tapered so as to form the die, and the upstream part of the printing head section has a same inner diameter as at least one of the feed section, the cooling section the backflow prevention section and the heating section. 
     
     
         11 . A method, comprising:
 performing three-dimensional printing with the three-dimensional printing system in accordance with  claim 1  to prepare the three-dimensional object made at least partially of an expanded polymer.   
     
     
         12 . The method in accordance with  claim 11 , wherein the performing three-dimensional printing includes
 providing polymer in the form of beads or filaments,   impregnating the polymer in the autoclave with a blowing agent at a temperature below a melting point of the polymer and at a pressure of 2 to 50 MPa for 1 minute to 48 hours so as to provide an expandable polymer mixture,   transferring the expandable polymer mixture into the feed section of the printing device,   cooling the expandable polymer mixture in the printing device,   e) heating the expandable polymer mixture in the printing device so as to obtain the expandable, expanding or expanded polymer melt, and   f) shaping, depositing and foaming the expandable, expanding or expanded polymer melt by extrusion through the die of the printing device.   
     
     
         13 . The method in accordance with  claim 11 , wherein the polymer is selected from the group consisting of thermoplastic polyurethanes, polyolefins, polyesters, ethylene vinylacetate copolymers, ethylene butyl acrylate copolymers, polystyrenes, polylactic acids, thermoplastic elastomers, nitrile rubbers, copolymers of acrylonitrile and butadiene, polychloroprenes, polyimides, polyvinyl chlorides and arbitrary combinations of two or more of the aforementioned polymers. 
     
     
         14 . The method in accordance with  claim 12 , wherein the blowing agent is a physical blowing agent. 
     
     
         15 . A three-dimensional object being obtained by the method in accordance with  claim 11 .